At the height of World War II, in 1942, the British Navy had a sudden breakdown in radio communications. The British became convinced that it was a German trick. It turned out to be disturbances caused by sunspots over 93 million miles away.

Carl Sagan's COSMOS is one of the most influential science programs ever made.

Q. Does the moon have a dark side?

A. The moon does have a far side which is impossible to see from the earth, but it doesn't mean that it's always dark. Each side of the moon is dark for no longer than 15 days at a time.

Q. Where does sound come from?

A. The air is always filled with sound waves. All things give off vibrations, but some have a low frequency which most cannot hear. The reason: it may take 3 minutes to make a single vibration. They may be caused by earthquakes and storms.

Did You Know?

The microwave was invented after a researcher walked by a radar tube and a chocolate bar melted in his pocket.

Coke-a-Cola was originally green.

Rubberbands last longer when refrigerated.

Cave Stalactites and Stalagmites
by Jeanette Cain

This project will require at least two weeks advance preparation to prepare a cave with stalactites and stalagmites. If you live in a damp or humid climate, your results will not be dramatic. In a real cave stalactites and stalagmites form when mineral rich water flows through porous rock. Through capillary action, which is the force of attraction between a solid and a liquid, mineral rich water flows through porous rock and begins to accumulate. Gravity will eventually force the water to drip out of the the rock. During the time the droplets hang, air will evaporate some of the water causing a mineral nucleus formation on which more droplets will hang.

For the formation of icicles, which resemble stalactites and stalagmites, super cooled water drips through the icicle and freezes around a nucleus of ice at the tip. Each droplet accumulates on another droplet until a stalactite is formed. As the stalactite grows and becomes large enough for water to flow through it again, the capillary action begins once more.

Stalactites hang from the top of a cave and stalacmites grow from the floor. They may also be found on bridges and buildings.

FIRST, cut a piece from the black poster board: 4 1/2 by 9 inches, or 11.25 x 22.5 centimeters. Bend this piece of board into a semicircle.

NEXT, put the 4 drinking glasses around the outside of the semicircle. Tape the ends of your semicircle to the outside of the glasses, checking to make certain the glass tops are at least 1 inch, or 2.5 cm, above the top edge of the poster board. If this isn't so, you will need taller glasses or you will need to trim your poster board.

THEN cut the black yarn into two 16-inch, or 40 cm, pieces, and tie the washers to the ends of each piece of yarn. You will need to stretch the yarn pieces ACROSS the glasses so that the pieces crisscross and lightly sag.

MIXING THE MINERAL SOLUTION

FIRST, take the saucepan and fill with water, add Epsom salt, and stir with the tablespoon until all the salt disolves. You will need to heat the water, without boiling, and continue to stir. You can now add more Epsom salt. AN ADULT will need to help you fill each glass with the warm Epsom salt solution. This is where the potholder is needed!

Be careful not to break the glasses. This is accomplished by SLOWLY pouring the solution into each glass.

You will now watch and observe your cave for about a week to see the changes taking place.